Ribbon loom with a weft insertion needle

ABSTRACT

A thread insertion needle for a ribbon weaving machine includes a needle body and a bracket, enclosing the needle body and having two parallel legs disposed on opposite sides of the needle body and forming with the needle body two slots, and a connector section connecting the two legs, with the connector being spaced from the needle body tip and defining with the body tip a free space for receiving therein filling threads for inserting them into a shed in addition to a filling thread received in the recess formed in the needle body tip.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention deals with a filling thread insertion or shootingneedle for a ribbon weaving machine as well as a ribbon weaving machineitself equipped with such a filling thread insertion needle.

Various embodiment forms of filling thread insertion needles are used inribbon weaving machines.

2. Description of the Prior Art

In the group of embodiment forms of filling thread insertion needles (EP0 121 648 B1, GB 1 424 301, GB 2 146 665 A) a hook exists for grippingthe filling thread to be inserted and a thread guide is provided foradditional filling threads. The thread guiding is accomplished through aslot, which extends essentially across the length of the needle. Thisslot can be configured within the needle or can be formed by the needlebody and a second member connected therewith. These embodiment formshave the following disadvantages in common: that the guidance isdisposed either above or below the needle body and consequently thefilling threads, which do not have to be inserted cannot form a shed andare carried along loosely similar to warp threads and also that afilling thread, which is not inserted over a larger distance, floats andbecomes visible at the edge of the fabric. This can indeed be partiallyprevented in that blind fillers are inserted, which is disadvantageous,since the overall productivity is thereby reduced, meaning the weavingoutput is lower and the thread consumption is greater. In addition suchblind fillers can impair the appearance of the fabric, in particularbecause loose dark figure or fancy threads appear as being translucentthrough light color weaves.

In another group of embodiment forms the filling thread insertion orshooting needles have only a hook at the needle tip, which is configuredon the needle at the bottom or the top. A guidance has not beenprovided. In these embodiment forms the shedding motion of thenon-inserted filling threads is possible. In this case it isdisadvantageous that the filling thread can be inserted only on oneside, which excludes the so-called pic-pic, and that a special laying-indevice is required, whereby the weaving speed is reduced because of theextremely rapid laying-in and picking-out motion.

Finally filling thread insertion or shooting needles are known (CH 16654 A5), which comprise a fork-shaped recess at the needle tip forgripping the filling thread to be inserted. With this filling threadinsertion needle any desired filling change is possible wherein howeverthe following disadvantages have to be accepted:

1. Sticking and crossed warp threads, which get into the effective rangeof the fork, are carried along as filling threads. Weaving errors andwarp thread breaks consequently occur.

2. The inserted filling thread is not pulled back by the needle sincethe fork is open towards the tip of the needle. Due to this a higherfilling thread tension must be provided which tends to increase thefilling thread breaks.

Both above phenomena have a disadvantageous or negative effect upon theproductivity of the ribbon weaving machine.

SUMMARY OF THE INVENTION

The invention wants to remedy or redress this state of affairs. Theinvention solves this task, by inserting or shooting one single fillingthread out of a number of the filling threads guided in the fillingthread insertion needle and by forming a shed out of the remainingfilling threads.

The invention affords expediently the possibility

of any random filling change pic a pic, meaning from above and below theneedle body;

to tie the non-inserted filling threads such as warp threads into theedge of the weave or tissue, thus making them invisible;

to control the reading-in of the filling thread and the shedding motionby a conventional Jacquard apparatus;

to use a color control device directly as a shedding motion devicewithout using any special motion sequence;

to tension of the lastly inserted filling thread and to produce a fineimpeccably tensioned stitch edge.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following the invention is described with the help of theenclosed drawings. It is shown on:

FIG. 1 a diagram of a portion of a weaving machine in side view;

FIG. 2 a presentation of a shed of the weaving machine in FIG. 1 duringinsertion of a filling thread;

FIGS. 3 to 5: an embodiment form of a filling thread insertion needle inthe invention in the course of filling thread insertion in threepositions, shown diagrammatically; and

FIG. 6 and 7: another embodiment form of a filling thread insertionneedle during filling thread insertion shown in two positions.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A driving device with an oscillating shaft 2 is provided at the frame 1of the weaving machine, at which shaft an arm 3 for a filling threadinsertion needle 4, 5 for insertion of filling threads into a weavingshed formed by the warp threads 15, 16 is fastened. A reed 6 isconnected to a drive shaft 8 through a drive lever 7 and performs areciprocating pivoting motion, in order to beat-up or loop an insertedfilling thread to the setting-on edge.

A shedding motion device 11 contains heddles 12 which are guided andaligned by harness or camber board 13. The heddles 12 comprise threadguides 14 by means of which the warp threads 15, 17 are moved up anddown in accordance with a preset program in order to form a weaving shed(FIG. 2). As is shown in FIGS. 1 and 2, filling threads 17, 18, 19 arefurthermore provided, which are movable up and down by the heddles 10,21 and 22 with the thread guides 23, in order to select the fillingthread 18 intended for insertion or shooting into the shed. This fillingthread 18 is thereby guided into the path of motion of the fillingthread insertion needle 4, 5 and after insertion it is beat up by thereed at the edge of the weave 9.

As FIGS. 3 to 6 show, the filling thread insertion needles 4, 5 consistof a needle body and a bracket, which are fastened to the arm 3 in acantilevered manner. The needle bodies have a V-shaped recess 30 at thefree end.

In the embodiment form shown in FIGS. 3 to 5 the needle body 31 isshaped like a circular arc and the curved bracket 32 has two legs 33extending in a parallel manner. The bracket is connected with its legends in the arm and encloses the needle body 31 in such a way, that aslot 34 exists respectively between the needle body 31 and the legs 33and spacing is provided between the free end of the needle body, 31 andthe connecting segment or section 35. The curved bracket 32 is formedadvantageously of a wire. The filling thread insertion needle 4 isdisposed in such a way in the arm 3, that the opening plane of the slots34 lies transversely to the plane of motion of the filling threadinsertion needle 4 (FIG. 2).

The mode of operation of the filling thread insertion needle 4 isdescribed with reference to FIGS. 3 to 5 at the example of three fillingthreads 17, 18, 19. The filling thread insertion needle 4 is shown inFIG. 3 in a position prior to insertion into the shed. Prior to theinsertion the filling thread 18 to be inserted is displaced by means ofthe heddle 21 (FIG. 2) into the path of motion of the needle body 31, sothat during the insertion motion the filling thread 18 can be placedinto the V-shaped recess 30 and can be gripped there by the needle body31. During the filling thread insertion only the selected filling thread18 is pulled through the shed formed by the warp threads, 15, 16, whilethe filling threads 17, 19, which have not been gripped, are conductedseparately from each other respectively into a slot 34 along the needlebody 31 and form a shed (FIG. 2). In the position shown in FIG. 4 thefilling thread insertion needle 4 has pulled the filling thread 18through the shed in order to transfer it to a diagrammatically showntie-up device 36. Subsequently the filling thread insertion needle 4 ispulled out of the shed and assumes the position shown in FIG. 5. In thecourse of this motion the remaining filling threads 17, 19 are pulled tothe side in the final phase, so that the inserted filling thread 18 cansubsequently be looped or beaten up by the reed 6.

Another embodiment form of a filling thread insertion needle 5 is shownin FIGS. 6 and 7, wherein the filling thread insertion needle is shownin FIG. 6 in a position prior to the start of the insertion process andis shown in FIG. 7 in the position after termination of the insertionprocess.

The filling thread insertion needle 5 has the same basic structure asthe filling thread insertion needle 4. The filling thread insertionneedle 5 consists of a straight needle body 51 and a bracket 52 with twostraight legs 53 and a V-shaped connector segment 54. The bracket 52 isfastened with its free ends to the needle body 51 in such a way, that astraight slot 55 exists respectively between the needle body 51 and thelegs 53 and that a spacing exists between the free end of the needlebody 51 and the connector segment 54.

The mode of operation of this filling thread insertion needle 5 is thesame as in the case of the filling thread insertion needle 4 describedin connection with FIGS. 3 to 5, so that a detailed description thereofdoes not need to be given.

I claim:
 1. A thread insertion needle for a ribbon weaving machine forinserting a plurality of filling threads, the thread insertion needlecomprising:a needle body having a tip and a recess formed in the tip forreceiving one of the plurality of filling threads; and a bracketenclosing the needle body and having two parallel legs disposed onopposite sides of the needle body and forming therewith two slots, and aconnector section connecting the two legs, the connector section beingspaced from the tip and defining therewith a free space for receivingtherein other of the plurality of filling threads.
 2. A ribbon wavingmachine, comprising a thread insertion needle for inserting a pluralityof filling threads, said needle having:a needle body having a tip and arecess formed in the tip for receiving one of the plurality of fillingthreads, and a bracket enclosing the needle body and having two parallellegs disposed on opposite sides of the needle body and forming therewithtwo slots, and a connector section connecting the two legs, theconnector section being spaced from the tip and defining therewith afree space for receiving therein other of the plurality of fillingthreads; and means for reciprocating the thread insertion needle forinserting the plurality of filling threads into a shed, and wherein anopening plane of the two slots lies transversely to a motion plane ofthe thread insertion needle.
 3. A ribbon weaving machine according toclaim 2, further comprising tie-up means for tying up the fillingthreads, wherein the connector section tensions the filling threads uponexiting of the thread insertion needle from the shed to facilitate tyingup of the threads.